1. Field of the Invention
The present invention relates to an ink reservoir, and more particularly to an ink reservoir having an ink level sensor for detecting the amount of ink stored in an ink supply tank which serves as an ink supply source to a print head.
2. Description of the Prior Art
In a prior art ink reservoir, portions of top and bottom sides of the ink supply tank are recessed to form a pair of recesses arranged so as to be horizontal relative to the ink level, a pair of sensors such as electrodes are arranged on the recesses, so that the sensors are disposed to be substantially parallel to the ink level (i.e., horizontal), and the ink level is detected by a change of the electrostatic capacitance between the electrodes.
However, in such an ink reservoir, when the ink remains on the inner sides of the recesses due to surface tension as the ink level lowers, or when the ink is deposited thereon as a result of vibration, the quantity of ink cannot be detected.